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What: Shares of the biotech Biogen Idec(NASDAQ:BIIB) briefly spiked by 10.8% this morning on high volume after providing an update for its closely watched Alzheimer's disease drug candidate aducanumab (BIIB037). At the the 12th International Conference on Alzheimer's and Parkinson's Diseases and Related Neurological Disorders being held in Nice, France, Biogen shared interim results from an early stage study showing that the drug led to a significant reduction in amyloid plaque levels, and exhibited a favorable safety profile.

So what: Alzheimer's disease has proven extremely difficult to treat, with 99% of experimental drugs failing to show any decrease in amyloid plaque levels over the last decade, despite promising pre-clinical studies. Biogen could thus have a game-changer on its hands. And if approved, this biological-based drug should rapidly ascend into the ranks of megablockbusters, given that over 5 million Americans and over 10 million people globally are presently afflicted with this devastating disease.

Now what: Based on these promising results, the company plans to accelerate aducanumab's development by pushing it straight into a pivotal late stage trial later this year. According to the press release, this new trial would include primary endpoints that could serve as the basis for a regulatory filing.

That's especially good news for Biogen investors, as some analysts believe a truly disease-modifying drug for this condition could generate up to $20 billion in peak sales. To be fair, most experts estimate peak sales for a new breakthrough Alzheimer's drug closer to $4 billion. But that's still impressive, making it an important experimental drug to keep an eye on going forward.

Author

George Budwell has been writing about healthcare and biotechnology companies at the Motley Fool since 2013. His primary interests are novel small molecule drugs, next generation vaccines, and cell therapies.